Identify the correct statements from the following : Choose the correct answer from the options given below:
- A, B and C Only
- A, B and D Only
- B, C and D Only
- A, C and D Only
Answer
(2) A, B and D Only
Solution
A. Correct – the uncertainty principle is significant for microscopic particles such as electrons.
B. Correct – for the same type of orbital, size increases with n, so 2px is smaller than 3px.
C. Incorrect – the energy of an orbital depends on the nuclear charge. As per NCERT, the energies of orbitals of the same subshell decrease with increase in atomic number (Z); so the 2s orbital of Li (Z = 3) is lower in energy than the 2s orbital of H (Z = 1).
D. Correct – Cr (Z = 24) is [Ar] 3d5 4s1 (extra stability of half-filled d subshell).
∴ Correct statements: A, B and D
Answer: (2)